#includeint main() { std::ostream os{std::cout.rdbuf()}; os << "Hello, world!"; if (os.fail()) { std::cerr << "An error occurred while writing to the stream" << std::endl; } return 0; }
#includeIn this example, a new `std::ofstream` object is created that writes to a file called "myfile.txt". `std::ofstream::is_open` is called to check if the file was opened successfully. If not, an error message is written to `std::cerr` and the program exits with an error status. A message is then written to the file, and `std::ostream::fail` is called to check if an error occurred. If so, an error message is written to `std::cerr`. Finally, the file is closed. In summary, `std::ostream::fail` is a member function of the `std::ostream` class in the C++ Standard Library. It is used to check if a failure has occurred on the stream. The function is defined in the `int main() { std::ofstream out_file{"myfile.txt"}; if (!out_file.is_open()) { std::cerr << "Could not open file" << std::endl; return 1; } out_file << "Hello, world!"; if (out_file.fail()) { std::cerr << "An error occurred while writing to the file" << std::endl; } out_file.close(); return 0; }